The geojson2h3 library includes a set of utilities for conversion between GeoJSON polygons and H3 hexagon indexes, using h3-js.
- Post bug reports or feature requests to the Github Issues page
- Ask questions by posting to the H3 tag on StackOverflow
npm install geojson2h3
import geojson2h3 from 'geojson2h3';
const polygon = {
type: 'Feature',
geometry: {
type: 'Polygon',
coordinates: [[
[-122.47485823276713, 37.85878356045377],
[-122.47504834087829, 37.86196795698972],
[-122.47845104316997, 37.86010614563313],
[-122.47485823276713, 37.85878356045377]
]]
}
};
const hexagons = geojson2h3.featureToH3Set(polygon, 10);
// -> ['8a2830855047fff', '8a2830855077fff', '8a283085505ffff', '8a283085506ffff']
const feature = geojson2h3.h3SetToFeature(hexagons);
// -> {type: 'Feature', properties: {}, geometry: {type: 'Polygon', coordinates: [...]}}
- geojson2h3
- .featureToH3Set(feature, resolution) ⇒
Array.<String> - .h3ToFeature(hexAddress, [properties]) ⇒
Feature - .h3SetToFeature(hexagons, [properties]) ⇒
Feature - .h3SetToMultiPolygonFeature(hexagons, [properties]) ⇒
Feature - .h3SetToFeatureCollection(hexagons, [getProperties]) ⇒
FeatureCollection
- .featureToH3Set(feature, resolution) ⇒
Convert a GeoJSON feature to a set of hexagons. Only hexagons whose centers fall within the feature will be included. Note that conversion from GeoJSON is lossy; the resulting hexagon set only approximately describes the original shape, at a level of precision determined by the hexagon resolution.
Kind: static method of geojson2h3
Returns: Array.<String> - H3 indexes
| Param | Type | Description |
|---|---|---|
| feature | Object |
Input GeoJSON: type must be either Feature or FeatureCollection, and geometry type must be either Polygon or MultiPolygon |
| resolution | Number |
Resolution of hexagons, between 0 and 15 |
Convert a single H3 hexagon to a Polygon feature
Kind: static method of geojson2h3
Returns: Feature - GeoJSON Feature object
| Param | Type | Description |
|---|---|---|
| hexAddress | String |
Hexagon address |
| [properties] | Object |
Optional feature properties |
Convert a set of hexagons to a GeoJSON Feature with the set outline(s). The
feature's geometry type will be either Polygon or MultiPolygon depending on
the number of outlines required for the set.
Kind: static method of geojson2h3
Returns: Feature - GeoJSON Feature object
| Param | Type | Description |
|---|---|---|
| hexagons | Array.<String> |
Hexagon addresses |
| [properties] | Object |
Optional feature properties |
Convert a set of hexagons to a GeoJSON MultiPolygon feature with the
outlines of each individual hexagon.
Kind: static method of geojson2h3
Returns: Feature - GeoJSON Feature object
| Param | Type | Description |
|---|---|---|
| hexagons | Array.<String> |
Hexagon addresses |
| [properties] | Object |
Optional feature properties |
Convert a set of hexagons to a GeoJSON FeatureCollection with each hexagon
in a separate Polygon feature with optional properties.
Kind: static method of geojson2h3
Returns: FeatureCollection - GeoJSON FeatureCollection object
| Param | Type | Description |
|---|---|---|
| hexagons | Array.<String> |
Hexagon addresses |
| [getProperties] | function |
Optional function returning properties for a hexagon: f(hexAddress) => Object |
The geojson2h3 library uses yarn as the preferred package manager. To install the dev dependencies, just run:
yarn
To run the tests in both native ES6 (requires Node >= 6) and transpiled ES5:
yarn test
To format the code:
yarn prettier
To rebuild the API documentation in the README file:
yarn build-docs
Pull requests and Github issues are welcome. Please include tests for new work, and keep the library test coverage at 100%. Before we can merge your changes, you must agree to the Uber Contributor License Agreement.
The geojson2h3 library is licensed under the Apache 2.0 License.